Abstract

The epitaxialgrowth of graphene on inexpensive, commercially available, free-standing polycrystalline 3 C-SiC has been achieved by solid state graphitization in ultrahigh vacuum. The structural and electronic properties of such epitaxialgraphene (EG) have been explored by Raman spectroscopy,scanning tunneling microscopy(STM), and scanning tunnelingspectroscopy (STS). The Raman results show that the grown EG is compressively stressed. The quality of such EG is similar to that on single-crystalline hexagonal SiC substrates. The STM measurements show that the EG grown on polycrystallineSiC presents atomically smooth surfaces across large regions of the underlying SiC substrate with some nanometer-scale features, such as one-dimensional (1-D) ridges, 1-D grain boundaries, and graphene in different stacking sequences. The STS measurements reveal the electronic properties of such EG at an atomic scale. Our approach suggests a more inexpensive way to grow high quality and large scale graphene and represents a promising step toward commercialization of graphene-based electronics.